/thirdparty/breakpad/processor/static_range_map-inl.h

  1// Copyright (c) 2010 Google Inc.
  2// All rights reserved.
  3//
  4// Redistribution and use in source and binary forms, with or without
  5// modification, are permitted provided that the following conditions are
  6// met:
  7//
  8//     * Redistributions of source code must retain the above copyright
  9// notice, this list of conditions and the following disclaimer.
 10//     * Redistributions in binary form must reproduce the above
 11// copyright notice, this list of conditions and the following disclaimer
 12// in the documentation and/or other materials provided with the
 13// distribution.
 14//     * Neither the name of Google Inc. nor the names of its
 15// contributors may be used to endorse or promote products derived from
 16// this software without specific prior written permission.
 17//
 18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 29
 30// static_range_map-inl.h: StaticRangeMap implementation.
 31//
 32// See static_range_map.h for documentation.
 33//
 34// Author: Siyang Xie (lambxsy@google.com)
 35
 36#ifndef PROCESSOR_STATIC_RANGE_MAP_INL_H__
 37#define PROCESSOR_STATIC_RANGE_MAP_INL_H__
 38
 39#include "processor/static_range_map.h"
 40#include "processor/logging.h"
 41
 42namespace google_breakpad {
 43
 44template<typename AddressType, typename EntryType>
 45bool StaticRangeMap<AddressType, EntryType>::RetrieveRange(
 46    const AddressType &address, const EntryType *&entry,
 47    AddressType *entry_base, AddressType *entry_size) const {
 48  MapConstIterator iterator = map_.lower_bound(address);
 49  if (iterator == map_.end())
 50    return false;
 51
 52  // The map is keyed by the high address of each range, so |address| is
 53  // guaranteed to be lower than the range's high address.  If |range| is
 54  // not directly preceded by another range, it's possible for address to
 55  // be below the range's low address, though.  When that happens, address
 56  // references something not within any range, so return false.
 57
 58  const Range *range = iterator.GetValuePtr();
 59
 60  // Make sure AddressType and EntryType are copyable basic types
 61  // e.g.: integer types, pointers etc
 62  if (address < range->base())
 63    return false;
 64
 65  entry = range->entryptr();
 66  if (entry_base)
 67    *entry_base = range->base();
 68  if (entry_size)
 69    *entry_size = iterator.GetKey() - range->base() + 1;
 70
 71  return true;
 72}
 73
 74
 75template<typename AddressType, typename EntryType>
 76bool StaticRangeMap<AddressType, EntryType>::RetrieveNearestRange(
 77    const AddressType &address, const EntryType *&entry,
 78    AddressType *entry_base, AddressType *entry_size) const {
 79  // If address is within a range, RetrieveRange can handle it.
 80  if (RetrieveRange(address, entry, entry_base, entry_size))
 81    return true;
 82
 83  // upper_bound gives the first element whose key is greater than address,
 84  // but we want the first element whose key is less than or equal to address.
 85  // Decrement the iterator to get there, but not if the upper_bound already
 86  // points to the beginning of the map - in that case, address is lower than
 87  // the lowest stored key, so return false.
 88
 89  MapConstIterator iterator = map_.upper_bound(address);
 90  if (iterator == map_.begin())
 91    return false;
 92  --iterator;
 93
 94  const Range *range = iterator.GetValuePtr();
 95  entry = range->entryptr();
 96  if (entry_base)
 97    *entry_base = range->base();
 98  if (entry_size)
 99    *entry_size = iterator.GetKey() - range->base() + 1;
100
101  return true;
102}
103
104template<typename AddressType, typename EntryType>
105bool StaticRangeMap<AddressType, EntryType>::RetrieveRangeAtIndex(
106    int index, const EntryType *&entry,
107    AddressType *entry_base, AddressType *entry_size) const {
108
109  if (index >= GetCount()) {
110    BPLOG(ERROR) << "Index out of range: " << index << "/" << GetCount();
111    return false;
112  }
113
114  MapConstIterator iterator = map_.IteratorAtIndex(index);
115
116  const Range *range = iterator.GetValuePtr();
117
118  entry = range->entryptr();
119  if (entry_base)
120    *entry_base = range->base();
121  if (entry_size)
122    *entry_size = iterator.GetKey() - range->base() + 1;
123
124  return true;
125}
126
127}  // namespace google_breakpad
128
129
130#endif  // PROCESSOR_STATIC_RANGE_MAP_INL_H__